The Local Group galaxies enable us to study the impact of metallicity on the structure and evolution of massive stars through spectroscopic analyses. However, color-based target selection for spectroscopy (in absence of known spectral types), though relatively successful, usually produces lists dominated by B-type modest-mass stars. We have

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The European Solar Telescope (EST) is a European collaborative project promoted by the European Association for Solar Telescopes (EAST) to build a high resolution 4m class solar telescope in the Canary Islands. Since 2008 to 2011 a Design Study has been developed to define the Conceptual Design of EST. During the Design Study, several preliminary

The solar chromosphere is an important boundary, through which all of the plasma, magnetic fields and energy in the corona and solar wind are supplied. Since the Zeeman splitting is typically smaller than the Doppler line broadening in the chromosphere and transition region, it is not effective to explore weak magnetic fields. However, this is not

The dwarf irregular galaxy IC10 in Cassiopeia, is the youngest available starburst galaxy and home to many X-ray sources. Using the Gemini multi-object spectrograph (GMOS), in the wavelength range containing H-alpha, we obtained spectra of twenty five stars that are positionally coincident with X-ray sources, at the 95% significance level. The

After a decade of intense studies using the latest X-ray and optical telescopes, the nature of ultraluminous X-ray sources (ULXs) is still largely unknown. No definitive answer has emerged on the question of the mass of the black hole powering these objects (intermediate-mass or supercritical stellar-mass?). Further, we lack even basic knowledge